The investigators are conducting this study to evaluate the impact and feasibility of a 12-week moderate-intensity aerobic and strength training exercise intervention, including a virtual component. The intervention includes brisk walking and moderate strength training, and involves home-based exercises, in-person sessions with an oncology-trained exercise physiologist, optional group training sessions, and weekly training goals. Participants will have access to a personalized web-based platform called Postwire, which will include videos of training sessions, and will allow participants to easily communicate with the study staff and with other study participants.